Concentration of phosphate-bearing material



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t Fatenteddune 3 193$ UNITED. STATES" WILLIAM TROTTER, OF NEW YORK, AND ELTOFT WRAY WILKINSON, OF QUEENS PATENT OFFICE LAGE, NEW YORK, ASSIGNORS TO MINERALS SEPARATION NORTH AMERICAN CORE PORATION, OE, NEW YORK, Y., A CORPORATION OF MARYLAND CONCENTRATION OF PHOSPHATE-BEARING MATERIAL 1T0 Drawing.

This invention relates to the concentration of phosphate-bearing material and herein illustrated as applied'to the concentration of phosphate-bearing rock Florida phosphate 5 pebble,

oleates of the amines. v ,I

It is found that certain -organic'soaps produced by the combination of a fatty acid and an amine, especially those which are made 0 from amines in which the nitrogen is coni tion agents.

' soaps made with oleic acid are highlyeffec- 'In the following tests the material used was-the reject from a sieving process of con centration of phosphate from No-11 mine of International Agricultural Corporation at 2 Mulberry, Florida, containing about 23 per cent of thephosphate known as bone phosphate of lime. This material was most-1y -;nesh' or finer and was deprived of most of its sliines, as this facilitated obtaining a richconcentrate and diminished the consumption of reagents.

. In one test thls material was made into a pulp with water and agitated in a minerals separation subaeration machine of the box 0 type,. and agitated with 2.5 pounds per ton f of a soap made by mixing equimolecular proportions of the alkyl amineknow'n as diethylamine, (G H )2NH, and oleic acid. 1 This product was soapy and was soluble in water.

3 It was added to the pulp in a five per cent solution. There was also added four'pounds per ton of a liquid substantially immiscible in water such as fuel oil. The resulting float was collected and was found to contain 68.8%

of bone phosphate of lime which was 85.7

5 when triethylamine was substituted for the y the aid of organic soaps such the- It has been found that such Application filed March 1, 1929, Serial No. 349,339.

diethylamine, but the "total recovery was a few percent smaller; I

In another test the soap was replaced by a soapmade from oleic acid and commercial 'triethanolamine, soluble under the conditions used and contalning about 3 parts of the hydroxy amine known as triethanolamine, 1 part dlethanolamine and a trace ofmonolethanolamine. The other conditions of this test-were identical. The resulting float was nected to a carbon atom carrying also at lea tcollected and found to contain 67.2% of bone two hydrogen atoms, are very effective flot'aphosphate of lime and which was 66.4% of the bone phosphate of lime in the crude ma-. 'terial treated.

same ore was used with the same amount of fuel oil, the soap in this case being dissolved in the fuel oil. The results are shown in the following table, the concentrates being retreated twice without addition of. reagents. B. P. L. represents bone phosphate of lime.

. B. P. L.

Weight B. P. L. recovery 1 Per cent Per cent Per cent Heads 100. 25.0 Concentrates 28. 0 65. 0 72. 8 1st middlin 33.4 9.0 12.2 2nd middlings 12. 2 15. 6 7. 6 Tails 26. 4 7. 4 7. 6

-' Other tests indicated that there was no material advantage in dissolving the soap in the oil, but that sometimes the best results were obtained when the base was first added 'to the aqueous pulp and the requisite fatty acid was added later in the theoretical proportions, so that the soap was made in situ.

Insome cases better results were obtained when, insteadpf adding equimolecular proa5. soap.

' n. P. L.

Weight B. P. L. meow,

Per cent Per cent Heads 24. 59 Concentrates 57. 6 81. 7 Tails 6. 9 18. 3

Another sample of the same phosphate- -bearing material was concentrated by agitation in an aqueous pulp with 2.5 pounds of the soap obtained when diethylamine reacted with equimolecular proportionsof stearic acid. It was found that excellent results 1 were obtained without the addition of fuel oilor other liquid immiscible with water. The crude ore added to the pulp contained about 23% of bone phosphate of lime. The

concentrate carried 69.8% of bone phosphate of limewhich was 53.8% of the bone phosphate of lime in the crude material treated.

If it is desired to obtain-a very rich concentrate the soap may be made with an amine and'with the distilled fatty acids of cocoanut oil instead of with oleic acid. The resulting flotation agent was found to yield a rich concentrate although .the recovery was found tobe less than with a corresponding oleic acid It has been found that in some'instances carbon tetrachloride may be substituted for the fuel oil.

Very good results were obtained when Tennessee phosphateearing material to be concentrated. Cassiterite and coal have been found to be amenable to concentration by this rocess. 4

Table tailings of the Anaconda Copper Mining Co. treated by this procedure yielded a hi h recoveryand a low grade concentrate capsule of being recleaned.

48.-mesh Calumet and Hecla table middlings from theregrinding plant, assaying about 6% native copper, treated .with 3 pounds er ton of diethylamine oleic acid soap wit the further addition of one-half pound of potassium xanthate per ton, yielded a concentrate assaying 40.6% copper, with a .recovery of 75.8% of the copper present.

Having thus described certain embodiments of the invention whatis claimed is :v

1. The process ofcpncentrating phosphatebearing material which conslsts 1n agltatmg a pul of the fine material w1th a soap produce by theeombination of fatty-acid and -an amine, and separating the float.

hosphate rock was used as the I bearing material which consists in agitating a pulp of, the fine material with a soap produced by the combination of-fatty acid and an amine in which the nitrogen is connected to a carbon atom which, carbon atom is connected to at least two hydrogen atoms, and separating the float.

3. The process of-concentrating phosphatei bearing material which consists in agitating a pulp of the fine material with a small quantity of a soap produced by thecombination of oleic acid with an alkyl amine, and separating the float.

4. The process of concentrating phosphatebearing material which consists in agitating a pulp of the fine'material with a small quantity. of a soap produced by the combination of oleic acid with an alkylamine, with the further addition of a liquid substantially inimiscible in water, and separating the float.

In testimony whereof, We have aflixed our signaturesto this specification.

WILLIAM TROTTER. ELTOFT WRAY WILKINSON.

2. 'The process of concentrating phosphate- 

